γ-ray sky seen by the Fermi LAT in a Mollweide projection. Panel a) shows the (total) photon flux reconstructed from photon count data of 6.5 years mission elapsed time in the energy range from 0.6 to 307.2 GeV reconvolved with the LAT’s IRFs. Panel b) shows solely the reconvolved diffuse contribution. Panel c) shows the fractional residual map between data and reconstruction smoothed with a 0.5° Gaussian kernel. Panel d) shows the fractional difference map between the standard total, Galactic plus isotropic, diffuse model (short “std”) and the reconstructed diffuse contribution.